Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Mechanical

This paper presents the use of multilayer perceptron (MLP) for fault diagnosis through a histogram feature extracted from vibration signals of healthy and faulty conditions of single point cutting tools. The features were extracted from the vibration signals, which were acquired while machining with healthy and different worn-out tool conditions. Principle component analysis (PCA) used to select important extracted features. The artificial neural network (ANN) algorithm was applied as a fault classifier in order to know the status of cutting tool conditions. The accuracy of classification with MLP was found to be 82.5 %, which validates that the proposed approach is an effective method for fault diagnosis of single point cutting tools. © 2018 International Institute of Acoustics and Vibrations. All Rights Reserved.

World University root node

School of Mechanical Engineering

Chennai Campus

The International Journal of Acoustics and Vibration

Condition Monitoring of Single Point Cutting Tools Based on Machine Learning Approach

Non-ferrous materials are widely used in industries, especially because of its corrosion resistance property. Among them Aluminium alloys are widely used because of its ease of machinability, good thermal Conductivity, less weight etc. Presently Aluminum is more used by industries than steel. Further Aluminium with alloy elements like copper, nickel, magnesium, tin etc. will enhance the properties of the materials and these alloyed elements have more industrial applications. Solution Treatment enhances the properties of these aluminium alloys. This work is focused on synthesis and characterization of hexenary aluminium Alloy (Al-Cu-Sn-Ni-Mg-Fe) by gravity die casting technique. The microstructure and wear behavior of as cast, solution treated alloys were elucidated by optical microscopy, pin-on-disc wear test. The mechanical properties were assessed by the tensile test, hardness test and compressive test. Solution treated aluminium alloy showed the remarkable improvement in wear resistance, hardness and tensile strength. The uniformly dispersed thermally stable θ and Ω phases in the aluminium matrix are one of the predominant factor in improving the hardness and tensile properties. The increase in hardness was achieved with solution treatment significantly reduced the wear rate. © 2006-2018 Asian Research Publishing Network (ARPN).

ARPN Journal of Engineering and Applied Sciences

Effect of solution treatment on microstructure, mechanical and wear characteristics of gravity die cast aluminium alloy

This paper presents an explicit work on developing a parallel manipulator for medical application. There are many applications in medicine that requires the technology of robotics like injecting electrodes, drilling of bone, medical transportation, to carry out different tests and so on. Surgeons divert their focus on improving the quality of the surgical procedure that includes accuracy, security, low morbidity and mortality. This work mainly concentrates on designing and developing a kinematic and dynamic model of parallel manipulator for bone drilling application which is required for prosthetics operations. According to the requirement of the application a three prismatic-universal-universal (3PUU) parallel manipulator is designed which rotates about x and y axis and translates along z axis. This research work involves in developing a conceptual design, deriving kinematics both inverse and forward, workspace and dynamics of the parallel manipulator. Inverse kinematics is obtained by the geometrical approach whereas inverse dynamics is obtained using Langrangian method. Further, the tool inverse kinematic solutions, overall workspace, dynamics of the three legs are determined. This study will help the researchers for the further development of parallel manipulators in medical assistance. © 2018 The Authors. Published by Elsevier Ltd.

VIT Unitversity

Fulltext

Procedia Computer Science

Kinematic and Dynamic Analysis of 3PUU Parallel Manipulator for Medical Applications

Port fuel injection is a proven technique in gasoline engine for its simplicity and cost effectiveness. This technique is a remarkable successor to conventional carburetors in reducing emission and improving transient performance. Nowadays, port injection technique is widely researched in Homogenous Charge Compression Ignition (HCCI), Premixed Charge Compression Ignition (PCCI) and Reactivity Controlled Compression Ignition (RCCI) systems, which reduce NOx and soot emission significantly. However, usage of high viscous fuels like diesel in the above techniques has to overcome various challenges like improper vaporization, wall wetting and poor atomization. This article aims to identify the way to obtain a typical diesel spray similar to that of gasoline spray in port injection by elevating the fuel temperature and injection pressure. The results show that the diesel spray at an elevated temperature of 80°C and an injection pressure of 4 bar looked similar to that of gasoline spray (at 33°C and 3 bar). Further experimental studies on engine was performed in Diesel-PCCI mode to study the influence of heated diesel over unheated diesel spray on engine performance and emissions. © School of Engineering, Taylor’s University.

Journal of Engineering Science and Technology

Experimental studies on premixed charge compression ignition (Pcci) engine using port injection of heated diesel

Tall buildings with complex designs have been the recent trend in the field of architecture and structural engineering. For t his kind of buildings, wind flow analysis is equally important as structural analysis since wind loads are dominant for these types of structures. Computational simulation (URANS) turbulent models of Computational fluid dynamics are widely used to study the external flow behavior of a bluff body and its influence of shape factors. Nowadays a variety of problems are occurring because of tall buildings environment like down drought wind, vortices, downwind effects, etc. Wind comfort and safety on and around tall buildings have become important parameters for architects and town planners who need guidelines and simplified tools to take account of wind in their buildings. The objective of this study provides more insight on wind flow over tall buildings with different geometry. In order to evaluate the wind flow around the building in terms of upstream wind, downstream wind, recirculation zones are quantified in terms of width (D) and surface pressure measurements were employed to all geometries. Numerical analysis has been performed in FLUENT software with k-ω SST model as solver. © 2018 Author(s).

AIP Conference Proceedings

Numerical simulation of tall buildings with various shape factors and investigation of its surrounding effect

The turbulent buoyant flows generated from a heat source block in a naturally ventilated cubical enclosure with vertical and horizontal openings are numerically investigated. Turbulence is modeled with large eddy simulation (LES) and the filtered governing equations are solved using an in-house code based on finite difference method (FDM). The time dependent flow characteristics are analyzed by varying the heat source aspect ratio (ϕ) in the range 0.25 ≤ ϕ ≤ 4.0 and the Grashof numbers (Gr) are varied between 107 ≤ Gr ≤ 1011. A chaotic flow behavior is observed inside the enclosure and the bidirectional exchange across the openings increases linearly with Grashof number. The results indicate that the heat source aspect ratio significantly impacts the thermal buoyancy force with the formation of multi-recirculating vortex cells inside the enclosure. A significant enhancement in the heat transfer rate and mass flow rates are observed after increasing the heat source aspect ratio. The results also indicate that the flow instabilities that develop across the vertical opening exceeded those across the horizontal opening. The present numerical results are in good agreement with the benchmark results reported in literature. © 2018 Elsevier Ltd

Building and Environment

Effect of heat source aspect ratio on turbulent thermal stratification in a naturally ventilated enclosure

The Cylinder head gasket (CHG) joint is the most important sealing joint for IC engine performance. Cylinder head bolt preload application should be stoichiometric. Excess cylinder head bolt pre-tension develops more stresses and extra bore deformation and insufficient cylinder head bolt pre-tension leads to gasket leakage. Uniform pressure distribution is required on cylinder head gasket but it is not possible because of varying stiffness of the head and block. Hence maximum pressure distribution is better for avoiding the leakages. Bore deformation, engine blow-by and lubricating oil consumption (LOC) of the engine minimum is better for achieving stringent emission norms. Influences of application method of preload, cylinder head bolt tightening pattern and number of passes are investigated on gasket pressure distribution, bore deformation, engine blow-by and LOC. FEA non-linear analysis is carried out for gasket pressure distribution and bore deformation. Piston and piston ring software is used for simulating engine blow-by and LOC. For optimizing controllable parameters Taguchi design of experiments method is used for robust and optimized design. Study reveals that tightening parameters influences are significant. This study is very important for IC engine efficiency improvement and engine CO2 emission reduction at design stage for new engine development program. © 2018 Praise Worthy Prize S.r.l.-All rights reserved.

International Review of Mechanical Engineering (IREME)

Cylinder Head Bolts Tightening Strategies Parameters Finalization by Taguchi Method for Multi Cylinder Engines

The effect of cobalt (0.5 wt%, 1.0 wt%, 1.5 wt% and 2.0 wt%), as an alloying element, on the microstructure and mechanical properties of W-Ni-Fe tungsten heavy alloy (WNF) prepared through spark plasma sintering (SPS) process is investigated in this work. The sintering is performed at 1400 °C with a heating rate of 100 °C/min and holding time for a period of 2 min. The properties of the cobalt added heavy alloys (WNFC) are found to be superior to that of the tungsten heavy alloy without cobalt addition. The 1.0% cobalt alloy is observed to give higher yield and tensile strengths compared to other alloys. As the mechanical properties of the alloys depend on the microstructural features, a detailed study on the influence of the microstructural parameters such as average grain size, contiguity and matrix volume fraction on the properties of the alloys is carried out. The average tungsten grain size of WNF alloy is 12.3 µm and that of WNFC alloys is from 9.5µm to 11.5 µm. The control of grain size is significantly evident in the case of spark plasma sintered alloys. The yield strength is found to be influenced by the W-grain size of the microstructure. The contiguity of the WNFC alloys is observed to decrease with increase in percentage of cobalt addition. The fractograph analysis of the tensile tested specimen helps in understanding the tensile behaviour of the alloys. The WNFC alloys show predominantly W-grain cleavage fracture compared to the WNF alloy, possibly due to the good cohesive strength of the matrix phase and W/matrix interface, because of cobalt addition and also due to the high heating rate followed in the SPS process. © 2017 Elsevier B.V.

Department of Design and Automation

Vellore Campus

Materials Science and Engineering: A

Microstructure and mechanical properties of spark plasma sintered tungsten heavy alloys

In this investigation, machining of composites, fabricated with randomly oriented chopped banana fiber of length 10 mm as reinforcement and hybrid polymer as matrix, is studied. Two hybrid polymers are used. One is made from 85% of isophthalic polyester and 15% of cashew nut shell liquid and the other is made from 85% of isophthalic polyester and 15% of cardanol. Conventional machining is carried out by taking three parameters (speed, feed and depth of cut) into consideration. Response surface methodology is used for design of experiments. Material removal rate (MRR) and surface roughness are investigated. © 2017 Elsevier Ltd.

Department of Manufacturing Engineering

Materials Today: Proceedings

Investigations on Machining of Banana Fibre Reinforced Hybrid Polymer Matrix Composite Materials

There is a continuous effort in reducing the sintering temperature and sintering time for synthesizing tungsten samples using different approaches. In this paper, spark plasma sintering (SPS) technique is used to consolidate pure tungsten of 10 micron average particle size at a lower temperature of 1200°C. For comparison, the tungsten compact is also sintered in a conventional furnace under vacuum condition. The microstructures of the samples sintered by both the processes indicate partial sintering of tungsten. The density, hardness and grain size measurements are recorded for the sintered samples and the results are compared for both sintered processes. The densities of the tungsten samples sintered through spark plasma sintering and conventional sintering are found to be 66.79 g/cm3 and 68.26 g/cm3 respectively. The hardness values follow the same trend as found in sintered density values. The average grain diameter of the tungsten grain does not show much variation between the processes. © 2017 Elsevier Ltd.